Monitoring of land cover change utilizing the change vector analysis approach: a Case study of al Najaf Province, Iraq
Analyzing information relevant to land cover changes is a fundamental issue in studies linked to environmental diversity. The use of multi-time satellite images at different scales allowed continuous observation of land cover changes. This work aimed to study changes in land cover in Al Najaf Province from satellite imagery, using the change vector analysis (CVA), through the last two decades (2000–2010 and 2010–2020). Enhanced Vegetation Index 2 (EVI2) and the Dry Bare Soil Index (DBSI) represented the vegetation and soil condition in the study region. They were estimated via Landsat satellite imageries for the years 2000, 2010, and 2020, then were considered the parameters for a land cover change analysis using the CVA. The outputs of CVA were assessed on maps of land cover obtained through the supervised classification for the mentioned above images. The results of the change vector magnitude found that the ratio of the changed area reached 46.58% and 56.35%, and the unchanged area was 53.42% and 43.65% for the periods (2000-2010) and (2010-2020), respectively. The results of the change direction revealed that the moisture reduction ratio was 26.93% and 4.85%, while the vegetation regrowth ratio was 15.81% and 38.79% for the same two periods, respectively. The results of the two considered periods exhibited that the (EVI2-DBSI) combination presented promising performance results regarding the overall accuracy of 0.90 and 0.92 and kappa index of 0.60 and 0.69, respectively.